Generally by putting something that would indicate that the person was some sort of staff in their title and signature. Then there was the climber poser mod that changed their title to Supreme back when the ranktext appeared below the title and actually fooled staff members into thinking he got a promotion. Another type of poser is the one that thinks that if they act like staff they'll become staff. Barking off at other members about rules and constantly PMing staff about other members breaking the rules. Often they are basing their accusations on a faulty interpretation of the rules...